Motor-controller



c. w. YER GER.

MOTOR CONTROLLER. APPLICATION FILED JUNE 23, l9l9. RENEWED MAY 21,1920.

Patented Dec. 28, 1920.

I N VEN TOR.

A TTORNEY UNITED STATES PATENT OFFICE.

CHARLES W. YERGER, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER- HAMMER MFG. ('30., OF MILWAUKEE, WISCONSIN, A CORPORATION OF WIS- CONSIN.

MOTOR-CONTROLLER.

Specification of Letters Patent.

Patented Dec. 28, 1920.

Application filed June 23, 1919, Serial No. 305.967. Renewed May 21, 1920. Serial No. 383,142.

To all whom it may concern Be it known that I, CHARLES IV. YERGER, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of lVisconsin, have invented new and useful Improvements in Motor-Controllers, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

This invention relates to motor controllers.

In my prior application, Serial No. 279,670, filed February 28, 1919, there is disclosed a method of controlling an electric,

motor by series and parallel commutations of the same resistance sections, and the present invention has among its objects to provide a simple and efficient controller for carrying out such method.

Another object is to provide a controller of the aforesaid character comprising a drum and coacting means enabling the drum to be reduced to an exceedingly simple and compact form.

Another object is to provide a controller of the aforesaid character comprising a drum and means-to protect said drum and the controlled motor against abnormal currents resulting from too rapid operation of the drum.

Various other objects and advantages of the invention will hereinafter appear.

The accompanying drawing illustrates certain embodiments of the invention which will now be described, it being understood that the invention may be embodied in other forms falling within the scope of the appended claims.

In the drawing,

Figure 1 diagrammatically illustrates a non-reversing controller; and,

Fig. 2 diagrammatically illustrates a reversing controller.

Referring to Fig. 1, the same illustrates a controller for accelerating a motor through the medium of resistances r, 1" and r and affording six steps of control. The

motor is shown as provided with an armature a and a series field 7, although it is to be understood that the motor might be of any other preferred type.

he controller includes a drum 1 comprising contact fingers 2, 3, 4 and 5 and 00- operating segments 2 3, 3 4, l and 5 These segments are all electrically connected and are so arranged that in the first position of the drum segments 2 and 3 engage fingers 2 and 3 respectively. Then when the drum is moved tosits second and third positions segments 4: and 5 are successively engaged with fingers 4 and 5, while in the fourth position of said drum all but segments 2 and 5- are disengaged from the fingers. Then when the drum is moved to its fifth position segment 3 is engaged with finger '3 and finally when the drum is moved to its sixth position segment 4 is engaged with finger 4:. Further, the controller includes a so-called lockout switch 6 having a shunt operating magnet 7 and a series lockout magnet 8.

The circuit arrangement is such that the drum in its first position completes circuit from line L through finger 2, segments 2* and 3 to finger 3 and thence through resistances r, r and r in series, by conductor 10 through the lookout coil of switch 6, by conductor 11 through the motor armature and series field to line L. This provides for starting the motor with all of the resistance in circuit, while upon movement of the drum to its second position segments 3 and 4 cooperate with fingers 8 and i to short circuit resistance r and upon movement of the drum to its third positi on segments 4 and 5 cooperate with contacts 4; and 5 to short circuit resistance 0 thereby providing for a gradual increase in the current supplied to the motor.

During the foregoing operation the circuit of the operating magnet of switch 6 is completed from line L through the drum and resistances 7" and 1" by conductor 12 to and through said magnet, by conductor 13 to line L but as the motor current flows through said resistances there is such a voltage drop across the latter as to render said magnet incapable of closing the switch against the opposing pull of lockout magnet 8. However, when segment 5 engages contact finger 5 it connects the magnet directly to line L, whereupon the switch 6 is rendered responsive as soon as the motor current is reduced to a given value following exclusion of the resistance 1*. Assuming switch 6 to so respond, movement of the drum to the fourth positionopens the short circuit connected to line L to and through resistance r, by conductor let through switch 6,-

by conductors l5 and 11 to and through the motor. This further increases the supply oi current to the motor and when the drum is moved to its fifth position circuit is completed from line L through finger 2, segments 2 and 8 and finger 3 to and through resistance 7 to conductor 14., thus placing resistance 1* in parallel with resistances r and r for further increasing the current supplied to the motor. Finally when the drum is moved to its sixth position segment l engages finger l thus establishing circuit from line L to conductor 14 through switch (3 to and through the motor thereby throwing the motor directly on the line. Should the drum be moved from its third position to its fifth position prior to response of switch 6, said switch upon responding would simultaneously "connect the resistances 1" and r in parallel with resistance r and should said drum be moved to its sixth position prior to response of switch 6, said switch when responding would e2:- clude resistance r without establishing the parallel connections described.

Thus after the removal of two steps of resistance iurther variation of the resistance is rendered dependent upon response of the switch 6 regardless of the operation of the drum and said switch functions to insure against further resistance variation until the motor current is reduced to a definite value. Furthermore in the event that the drum is moved so rapidly as to curtail the number of steps the resulting increased current is handled by the switch 6, thus protecting the contacts of the drum.

Referring te Fig. 2 the same shows a controller, which is identical with that shown in Fig. 1, except for the addition of contact fingers and segments to the drum providing for operation thereof to reverse the flow of current through the motor armature. In this instance the drum is provided with contact fingers 20 to 24 with which cooperate opposed sets of segments 20, 21, 21 22 22 and 23 to establish the control circuits above described upon reverse operations of the drum. Further, the drum includes contact fingers 24C, 25, 26, 27 and 28 and cooperating segments 25, 26, 27 28, 2-1", 25*, 26 and 27 These fingers and segments are so arranged that upon movement of the drum in one direction segments 25 to 28 engage contacts 25 to 28 respectively, whereas upon movement 01 the drum in a reverse direction segments 2? to 27 engage fingers 24 to 27 respectively. Segments 25 and 26 are interconnected and when in engagement with fingers 25 and 26 connect the right hand terminal of the motor armature to the resistance, while segments 27 and 28 are interconnected, and when in engagement with fingers 27 and 28 connect the left hand terminal of the motor armature to the series field. On the other hand, segments 2- 3 and 25 are interconnected and when in engagement with fingers 24 and 25 connect the right hand terminal of the motor armature to the series field, while segments 26 and 27 are interconnected and when in engagement with fingers 26 and 27 connect the left hand terminal or" the armature to the resistance.

More specifically describing the connections movement of the drum direction. of the arrow establishes circuit from line L to contact finger 20, thence through segments 20 and 21. to linger 21, by conductor through resistances 7", r and r in series, by conductor 31 to the lookout winding of switch 6, by conductors 32 and 33 to finger 26, thence through ments 26 and 25 to finger 25, by conductor through the motor armature from right to left, by conductor 35 to linger 27, thence through segments 27 and 28 to finger 28, by conductor 36 through the series field, by

circuit in the conductor 37 to line L. On the other hand,

when the drum is moved in a reverse direction circuit is completed from line L through the left hand drum segments to conductor 30 and thence through the resistance and lockout coil and by conductors and 83 to contact finger 26, thence through segments 26 and 27 to finger 27, by conductor 85 through the motor armature from left to right, by conductor 3% to finger 25, thence through segments 25 and 243 to finger 24:, by conductors 3S and 36 through the series field to line L. The remaining circuits established by the drum and switch 6 are identical with those above described.

hat I claim as new and desire to secure by Letters Patent is:

1. In a motor controller, in combination, a plurality of series connected resistance sections and means including a manually operable contact device and a power operated switch, for first excluding certain of said. resistance sections from circuit and thereafter paralleling the same with other of said resistance sections, said switch being operable onlyatter exclusion of certain of said resistance sections and the establishment of parallel connections being dependent upon prior operation of said switch.

2. In a motor controller, in combination, a plurality of series connected resistance sec tions and means including a manually operable contact device and a power operated switch, for first excluding certain of said resistance sections from circuit and thereafter paralleling the same with other of said resistance sections, said switch being operable only after exclusion of certain of said resistance sections and the establishment of parallel connections being under the direction of said manual device but being dependent upon prior operation of said switch.

3. In a motor controller, in combination, a plurality of series connected resistance sections and means including a manually operable contact device and a power operated switch, for first excluding certain of said resistance sections from circuit, then establishing parallel connections for certain of said resistance sections and finally excluding all of said resistance sections from circuit, said switch being operable only when the motor current is confined within a given limit and its operation being a condition precedent to accomplishment of the last two mentioned functions of said means.

at. In a motor controller, in combination, a plurality of series connected resistance sections and means including a manually operable contact device and an electromag netic switch, for excluding certain of said resistance sections from circuit, then paralleling certain of said resistance sections and finally excluding all of said resistance sections under the direction of said contact device, said electromagnetic switch being responsive upon exclusion of a given number of said resistance sections but only when the motor current is confined within a predetermined limit and said contact device being inefiective to further control said resistance sections during delay in response of said switch.

5. In a motor controller, in combination, a plurality of series connected resistance sections and means including a contact drum and an electromagnetically controlled switch for first excluding certain of said re sistance sections from circuit, then establishing parallel connections for certain of said resistance sections and finally excluding all of said resistance sections from circuit, said drum being operable to perform said first mentioned function prior to operation of said switch and being thereafter operable to perform the last mentioned functions but only after prior operation of said switch, said switch being subject to control by the motor current to insure against response thereof while the motor current exceeds a predetermined value.

6. In a motor controller, in combination, a plurality of series connected resistance sections, a contact drum to exclude certain of said resistance sections from circuit, a switch adapted to automatically respond when said drum is so operated to render said drum further operable to establish parallel connections for certain of said resistance sections and to thereafter exclude all of said resistance sections from circuit.

7. In a motor controller, in combination, a plurality of series connected resistance sections, a contact drum operable to exclude certain of said resistance sections from circuit and an electromagnetic switch associated with said drum to render the latter further operable to establish parallel con-.

nections for certain of said resistance sections and to thereafter exclude all of said resistance sections from circuit, said switch being operable to so function only when the motor current is confined within a. predetermined limit.

8. In a motor controller, in combination, a plurality of series connected resistance sections and an electromagnetic switch for controlling the same, said drum being operable independently of said switch to exclude a limited number of said resistance sections from circuit and thereafter operable to connect certain of said resistance sections in parallel and to exclude all of said resistance sections from circuit but only after response of said switch, said switch having an operating winding tending to effect response thereof upon movement of said drum to a given position and also having means to delay its response so long as the motor current exceeds a predetermined value.

In witness whereof, I have hereunto subscribed my name.

CHARLES W. YERGER. 

